1. Field of the Invention
The invention generally relates to an optical component and a light source apparatus, and more particularly, to a light guide plate (LGP) and a light source apparatus adopting the LGP.
2. Description of Related Art
A side type light source module usually includes an LGP, wherein the LGP functions to guide the scattering direction of a light beam produced by a light source so as to ensure the uniformity of the luminance of the light-emitting surface and convert a point light source or a line light source into a planar light source. In general speaking, an LGP includes a plurality of micro-structures to destroy total internal reflection (TIR) so as to make the LGP provide a uniform surface light source at the light-emitting surface. As a result, the LGP may emit light uniformly by the design of micro-structures.
Since the radiation pattern of emitting-light of most LGPs is unable to be effectively controlled and most ones of them are emitting-light with half floodlight radiation pattern, so that a glare is caused in the lighting apparatus application, and the glare makes the user have uncomfortable sense. In addition, although a few of current LGPs have light-controlling effect, however only the emitting angles in two directions of a light source may be controlled, but it fails to completely control the emitting angles of the light source.
Taiwan Patent No. M243656 discloses an LGP, wherein an array of concentric circle grooves are disposed on the light-emitting surface of the LGP. Taiwan Patent No. I241441 discloses an LGP, wherein the bottom surface of the LGP includes a plurality of V-shaped grooves and the height of a top portion of the V-shaped grooves is increased with an increasing distance between a V-shaped groove and the light incident surfaces.
U.S. Pat. No. 7,025,482 discloses an illumination device, wherein the surface of the light guide component has a plurality of concentric circle grooves. Taiwan Patent No. 509605 discloses a micro-forming cutter capable of cutting a concentric circle 3-D structure on a work piece to be processed. US Patent Application Publication No. 20060050200 discloses a prism plate, wherein the surface thereof has a ring-shaped prism composed of a plurality of concentric circle grooves. U.S. Pat. No. 4,105,293 discloses a light source base with guiding light, and the light source base includes an LGP with a circle light-emitting surface and a plurality of light sources surrounding the LGP.